• 공업화학
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• 제20권6호
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• pp.593-602
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• 2009

오랫동안 슈퍼옥사이드 음이온 라디칼(superoxide anion radical)은 활성산소(reactive oxygen species, ROS) 화학종으로서 물리화학적 기초 연구에서부터 생명과학(혹은 생명공학) 분야에 이르기까지 상당한 관심의 대상이었다. 최근에는 고도산화공정(advanced oxidation processes, AOP, 혹은 advanced oxidation technologies, AOT)을 이용하는 오염물 제어 분야뿐만 아니라 나노물질에 의한 유해성을 평가하는데 있어서 슈퍼옥사이드 음이온 라디칼이 중요한 화학종으로 주목을 받고 있다. 그럼에도 불구하고 슈퍼옥사이드 음이온 라디칼에 대한 명확한 이해가 부족하여 관련 연구자들 사이에서 불필요한 논쟁과 혼동을 일으키고 있으며 슈퍼옥사이드 음이온 라디칼의 물리화학적 성질에 대한 오해를 가중시키고 있다. 이 글에서는 기존 연구에서 행해진 슈퍼옥사이드 음이온 라디칼의 물리화학적 특성 및 그 반응성에 대해 정리하였고 고도산화공정, 나노물질 및 생명공학 분야 등에서 슈퍼옥사이드 음이온 라디칼이 갖는 중요성을 서술하였다.

• Toxicological Research
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• 제26권4호
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• pp.321-327
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• 2010

The ability of 80% ethanol extracts from five medicinal plants, Aralia continentalis, Paeonia suffruticosa, Magnolia denudata, Anemarrhena asphodeloides, and Schizonepeta tenuifolia, to neutralize hydroxyl radical, peroxyl radical and peroxynitrite was examined using the total oxyradical scavenging capacity (TOSC) assay. Peroxyl radical was generated from thermal homolysis of 2,2'-azobis(2-methylpropionamidine) dihydrochloride (ABAP); hydroxyl radical by an iron-ascorbate Fenton reaction; peroxynitrite by spontaneous decomposition of 3-morpholinosydnonimine N-ethylcarbamide (SIN-1). The oxidants generated react with $\alpha$-keto-$\gamma$-methiolbutyric acid (KMBA) to yield ethylene, and the TOSC of the substances tested is quantified from their ability to inhibit ethylene formation. Extracts from P. suffruticosa, M. denudata, and S. tenuifolia were determined to be potent peroxyl radical scavenging agents with a specific TOSC (sTOSC) being at least six-fold greater than that of glutathione (GSH). These three plants also showed sTOSCs toward peroxynitrite markedly greater than sTOSC of GSH, however, only P. suffruticosa revealed a significant hydroxyl radical scavenging capacity. Seven major active constituents isolated from P. suffruticosa, quercetin, (+)-catechin, methyl gallate, gallic acid, benzoic acid, benzoyl paeoniflorin and paeoniflorin, were determined for their antioxidant potential toward peroxynitrite, peroxyl and hydroxyl radicals. Quercetin, (+)-catechin, methyl gallate, and gallic acid exhibited sTOSCs 40~85 times greater than sTOSC of GSH. These four components also showed a peroxynitrite scavenging capacity higher than at least 10-fold of GSH. For antioxidant activity against hydroxyl radical, methyl gallate was greatest followed by gallic acid and quercetin. Further studies need to be conducted to substantiate the significance of scavenging a specific oxidant in the prevention of cellular injury and disease states caused by the reactive free radical species.

• Food Science and Biotechnology
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• 제15권3호
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• pp.357-362
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• 2006

We assessed various antioxidant activities, such as 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, 2,2'-azino-bis 3-ethylbenz-thiazoline-6-sulfonic acid (ABTS) radical, and reactive oxygen species (ROS) radical scavenging effect, along with antioxidant capacity, of soybean oil with added Citrus species peel extracts (CPEs). These extract oils showed higher radical scavenging effects than grape fruit seed extract, the natural antioxidant agent, did. When CPEs were added to soybean oil, they showed peroxide value (POV) and acid value (AV) increasing inhibition effects. Furthermore, none of the CPEs showed any cytotoxicity over the tested concentration range of 0.01-100 ppm. The major flavonoid contents of Citrus junos, as determined by HPLC, were naringin ($7.5\;{\mu}g/mg$) and neohesperidin ($7.5\;{\mu}g/mg$), and those of Citrus unshiu were narirutin ($3.13\;{\mu}g/mg$) and hesperidin ($1.97\;{\mu}g/mg$). However, the aglycone form was not found. This study showed that CPEs might be a potent source of natural antioxidant, without any toxic effects.

• 한국자원식물학회지
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• 제21권1호
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• pp.91-95
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• 2008

본 연구에서는 ${O_2}^-,{\cdot}OH$ radical, NO, $ONOO^-$ 자유라디칼을 유발시키는 in vitro assay system과 free radical-induced oxidative stress에 의한 단백질 손상에 대한 진흙버섯속에 속하는 상황버섯 물 추출물의 항산화 효과를 측정하였다. 상황버섯 물 추출물의 ${O_2}^-,{\cdot}OH$ radical, NO, $ONOO^-$ 자유라디칼 억제효과에서는 실험에 사용된 양성 대조물 보다는 낮게 나타났으나 모든 실험계에서 대조군에 비해 뚜렷하게 자유라디칼 소거효과를 나타냈다. 또한 상황버섯 물 추출물은 산화적 스트레스에 의한 단백질 손상 억제효과에서도 대조군에 비해 명확한 저해효과를 나타냈다. 그러므로 상황버섯의 항산화 효과는 상황버섯의 약리학적 효능을 설명하는데 중요한 기초 자료라고 사료된다.

• Applied Biological Chemistry
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• 제46권1호
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• pp.32-38
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• 2003

시판되고 있는 두류 13종류의 70% 에탄을 추출물을 제조하여, 이들의 항산화 활성을 환원력, 지질과산화 억제 활성, superoxide radical 소저활성, hydroxyl radical 소거활성, mitomycin C로 유도된 DNA의 산화적 손상에 대한 억제활성을 지표로 조사하였다. 환원력은 예팥, 속피리, 유월콩 및 적두가 높았다. 지질과산화 억제능을 조사한 결과, linoleic acid 자동산화계를 이용한 실험계에서 모든 시료가 억제활성을 보인 반면, 토끼 적혈구막 지질과 산화에 대한 억제활성은 쥐눈이콩과 적두, 속피리에서만 관찰되었다. Superoxide radical 소거활성은 예팥, 나물콩, 적두, 쥐눈이콩에서 높게 나타났으며, hydroxyl radical 소거활성은 속피리, 청태, 예팥과 제비콩에서 높았다. Mitomycin C로 유도된 DNA의 산화적 손상에 대한 억제활성을 조사한 결과, 모든 품종들이 DNA의 산화적 손상을 억제할 수 있었으나, 특히 예팥, 쥐눈이콩, 나물콩, 녹두, 적두의 억제활성이 우수하였다. 이상의 실험결과에서 예팥, 적두, 쥐눈이콩, 속피리가 환원력, 지질과산화 억제, superoxide radical 및 hydroxyl radical 소거활성, DNA의 산화적 손상에 대한 억제활성 둥 항산화활성이 우수한 품종임을 알 수 있었다.

• 화훼연구
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• 제17권3호
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• pp.158-164
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• 2009

본 연구는 불과 80% 에탄올 용매가 마가렛트, 큰금계국, 저먼캐모마일 및 알프스민들레 꽃 추출물의 항산화효과에 미치는 영향을 탐색하기 위해서 수행하였다. 추출수율은 물 추출물에서 27.15~40.25%, 80% 에탄올 추출물에서 24.92~42.84%로 나타났다. 총 폴리페놀 및 총 플라보노이드의 함량은 4종 모두 80% 에탄올 추출물에서 많게 나타났으며, 큰금계국 꽃의 80% 에탄올 추출물에서 함량이 가장 많았다. 4종 꽃 추출물의 DPPH radical 소거능, ABTS radical 소거능 및 $Fe^{2+}$ chelating 효과는 모두 80% 에탄올 추출물에서 높았다. DPPH radical 소거능은 알프스민들레 꽃의 80% 에탄올 추출물에서 기장 높았으며, 합성 항산화제인 BHT 보다 소거활성이 높았다. ABTS radical 소거능은 저먼캐모마일 꽃의 80% 에탄올 추출물에서 가장 높았다. 국화과 꽃 추출물은 DPPH radical 보다는 ABTS radical 소거능이 우수하였으며, 저먼캐모마일과 큰금계국 꽃의 80% 에탄올 추출물의 ABTS radical 소거능은 ascorbic acid와 BHT 보다 우수하였다. $Fe^{2+}$ chelating 효과는 알프스민들레 꽃의 80% 에탄올 추출물에서 기장 우수하였다. EDTA와 chelating 효과를 비교한 결과, 4종의 꽃 추출물은 EDTA 보다 chelating 효과가 극히 낮았다. 본 연구의 결과, 마가렛트, 큰금계국, 저먼캐모마일, 알프스민들레 등 국화과 4종의 꽃을 이용하여 천연 항산화제를 개발할 때에는 80% 에탄올을 용매로 추출하는 것이 시료의 항산화 물질 추출 효율 및 항산화 활성을 증가시킬 수 있는 효율적인 방법으로 생각된다.

• Journal of Applied Biological Chemistry
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• 제43권3호
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• pp.156-160
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• 2000

The possible mechanism of the DNA strand breaking activity of the hot-water extract of Fructus Chaenomelis (dried fruit of Chaenomeles sinensis) in a closed circular duplex replica form DNA (RFI DNA) was studied through agarose gel electrophresis under various conditions. Induction of DNA strand scission by the hot-water extract of C. sinensis occurred in dose and time-dependent manners. $Cu^{2+}$ was indispensable for the induction of DNA strand breakage. Exogeneous chelating agents inhibited the DNA breaking activity, conforming the catalytic action of $Cu^{2+}$ on generation of free radicals responsible for oxidative damage. Antioxidant enzymes and some radical scavengers were used to investigate the major radical species triggering the DNA strand scission, demonstrating that a highest inhibitory activity was found in the presence of catalase, while less in the presence of tiron (a scavenger for superoxide radical), 2-aminoethyl-isothiuroniumbromide-HBr, cysteamine (scavengers for hydroxyl radical), and 1,4-diazabicyclo [2,2,2] octane (a scavenger for singlet oxygen) in decreasing order. The findings implied that oxygen radical species generated in presence of transition divalent cation during the oxidation of some compounds contained in the hot-water extract of C. sinensis is mainly responsible for inducing genotoxicity.

• Journal of Species Research
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• 제10권2호
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• pp.159-163
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• 2021

Saussurea albifolia, a new species, is reported from the Baekdudaegan Mountains. It has distinctive morphological characteristics that distinguish it from other congeneric species of Saussurea in Korea; radical leaves persist or withered till flowering, white tomentose leaf beneath, campanulate involucre with brown-cobwebby hairs, and dark purplish phyllaries with acuminate tips. Saussurea albifolia is a new, endemic species, narrowly restricted to the Korean Peninsula as a consequence of adaptation to alpine or subalpine environments of the Baekdudaegan Area. Among the Korean species of Saussurea, S. gracilis Maxim., S. insularis Kitam., and S. seoulensis Nakai are morphologically similar to S. albifolia by having leaves with white hairs beneath and persistent radical leaves during blooming period. It has been well understood that Saussurea is one of the highly diversified and adaptable groups in Asteraceae and also that the currently recognized species in Korea likely significant underestimates its diversity on the Korean Peninsula.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.254.1-254.1
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• 2014

Atmospheric plasma's electron temperature is less than thermal plasma, so it is useful at bio experiment. We have investigated the optical emission spectroscopy (OES) lines by spectrometer during Atmospheric plasma bombardment onto the PBS surface by using an Ar gas flow. Also we have measured the OH radical density inside the solution induced by the Atmospheric plasma bombardment. OH radical species are appeared at 308 nm and 309 nm. Densities of OH radical species has been found to be significantly decreased versus depth of the solution from 2 mm to 6 mm. OH radical density inside the PBS is measured to be about $1.87{\times}1016cm-3$ downstream at 2 mm from the surface under optimized Ar gas flow of 200 sccm in Atmospheric plasma. Also we have investigated cell viability of lung cancer and normal cell after Atmospheric plasma treatment for fixed exposure time in 60 seconds, but different depths. We used SEM, we observed change of cell morphorogy, did experiment about FDA & PI Staining method. It is found that there is selectivity between the lung cancer and lung normal cell, in which cancer cell definitely has higher cell death ratio more than normal cell. We have investigated change of bond structure in FT-IR spectroscopy, the following peaks were observed: and intense O-H peak at 3422 cm-1 and at 2925 cm-1 corresponds to C-H stretch vibrations of methylene group.

• Journal of the Korean Wood Science and Technology
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• 제31권6호
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• pp.40-44
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• 2003

This study was carried out to investigate the antioxidant activities of domestic trees grown in Korea. Based on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity method, the methanolic extracts of 23 species were screened in order to search for natural antioxidants. Among these species, Acer ginnala, Cotinus coggygria, Acanthopanax koreanum, Thea sinensis and Pinus densiflora showed stronger antioxidative activity comparing with reference compound, ascorbic acid.